Regional paleo-environment for Carbonates Reservoirs at Campos, Santos and Espírito Santo Basins.

Dr. Sergio Antonio Cáceres Contreras – UNESPetro/ FUNDUNESP Dr. Maria Gabriela Castillo Vincentelli – UNESPetro / FUNDUNESP Leonardo Habermann - UNESP

Copyright 2017, SBGf - Sociedade Brasileira de Geofísica mentioned parameter could condition a carbonatic bank evolution or the sediment rework that nowadays is find in This paper was prepared for presentation during the 15th International Congress of the Brazilian Geophysical Society held in , , 31 July to 3 August, 2017. an oil accumulation.

Contents of this paper were reviewed by the Technical Committee of the 15th International Congress of the Brazilian Geophysical Society and do not necessarily This point of view will offer to geologists and represent any position of the SBGf, its officers or members. Electronic reproduction or geophysicists information about hydrocarbon habitat, and storage of any part of this paper for commercial purposes without the written consent of the Brazilian Geophysical Society is prohibited. some hypotheses about paleo-environment necessary to ______understand to the permo-porous system will be related to Abstract this information.

The study area is located at the Santos, Campos and Nowadays, it is well known that the comprehension of the Espírito Santo basins, all of them knowledge as Brazilian tectonic-structural evolution and the processes that marginal basins at the offshore region, as showed at the determines the presence of a carbonatic reservoir facies, figure 1. will be a technical way to understand depositional and diagenetic process; and as consequence, the hydrocarbon habitat for this kind of play would be defined. The objective is to define the hydrocarbon habitat at the Aptian levels of Campos, Santos and Espirito Santo basins, all the analysis based on tectonic-sedimentary techniques, seismic attributes, and seismic interpretation integrated with petrographic and petrophysical data. The regional seismic interpretation verified: a.- the presence of a proximal high confirmed at the gravimetric map; b.- The structures deforming stratigraphic levels older than Aptian; c.- the ends of the Aptian age is represented by a transition phase identified at the literature as “sag”. When evaluated the tectonic-structural context at the rift phase using geophysical data gravimetric map (Bouguer Anomalies) and seismic data, it is possible to define mainly three production hydrocarbon systems: a.- Reservoirs in – “Coquines” with good permeability and oil production initialized; b.- Reservoirs in limestone “Coquines” without initialized oil production; and, c.-Carbonates type limestone: stromatolites and laminated microbialites. Finally, the Figure 1. Study area: Santos, Campos and Espirito Santo identification of a fault system that affected the Aptian basins. level and the Post-Salt section were determinant for the oil migration at the basin, from the Jiquia Formation to the At Campos basin the main region that produce Aptian-Coquines and upper reservoirs. hydrocarbon from “Coquina” reservoirs is related to the

trend Enchova-Linguado-Trilha and Pampo. Vincentelli, et Introduction al. (2016) defined the lateral boarder of this province with

two fault systems with tectonic reactivation: Alegre fault The understanding of the geological factors, that define (at Northeast) and High Cabo Frio 2 fault (at Southwest); the petroleum habitat for Carbonates reservoirs, in addition, the authors call the attention to Polvo oil field would be based on a geophysical vision. that produce from Quissamã Fm. (Albian – Calcarenites), and it is located at the junction of the last mentioned fault The proposed research includes a regional (Santos, and Marlin fault (defined at the same research), with Campos and Espirito Santo Basins) geophysical azimuth NE-SW interpretation with the aim of verify the paleo-geometry and paleo-bathymetric conditions of the basement and Currently, it is well known that the comprehension of the sedimentation along Aptian and Albian ages. The tectonic-structural evolution and the processes that

Fifteenth International Congress of the Brazilian Geophysical Society REGIONAL PALEO-ENVIRONMENTS AT APTIAN COQUINE RESERVOIRS ______2 determines the presence of a carbonate reservoir facies, Rangel & Martins (1998) defined the main structural will be a technical way to understand depositional and features identified at the rift phase of these basins as diagenetic process, and as consequence the hydrocarbon showed at the figure 2. The Badejo High, big horst with habitat for this kind of play will be defined. main azimuth Northeast-Southwest, controlled the sedimentation between the middle and external platform The main objective is to define the hydrocarbon habitat at at the South and Southwest of Campos basin. In a the Aptian levels of Campos, Santos and Espirito Santo parallel position of Badejo High the Central and External basins, all the analysis based on tectonic-sedimentary highs were defined as horsts structures, separated by techniques, seismic attributes, and seismic interpretation normal faults that shows vertical slip until 2500 meters. integrated with petrographic and petrophysical data. The azimuth of the main fault system is NE-SW, the same that the Pre- recognized lineaments. Adjacent to The evolution of the Brazilian offshore basins, started with the main structural highs some structural lows like the breaking and as consequence the Atlantic Corvina-Paraty and São João da Barra, were described. Ocean opens and the American and African continent were separated. Until today, multiples studies oriented to define evolutive and sedimentary geological models based on the geological geophysical integration have been done, but a specifically study related to define pelo- environments base on the mentioned data has not yet been performed

The importance of integrated structural and stratigraphic models is related to the genesis of the own basin, because it represents the basement evolution history, fundamental in the comprehension of paleo-environment conditions to development carbonate reservoir like Coquinas at the Aptian age. At the next paragraphs some important consideration that justify this research are described:

Castro (2006) shows the importance of the pre-salt section analysis at Campos basins that contains some analogies with as follow: : “... the coquina reservoir at Laoga Feia Formation, in the Badejo, Pampo Figure 2: Main structural features identified at the rift phase and Linguado oil fields, is considered a unique oil trap, of the study basins. Rangel & Martins. (1998). where the control is mixed, in other words structural and stratigraphic and mainly diagenetic. The antithetic faults, inherited from the post- rift, conditioned the coquina Database and Methods distribution, promoting the section growing at the hanging wall, and it acts as conduct for the circulation of meteoric 2D regional seismic lines were interpreted joint with 3D water associated with the post-coquine unconformity that seismic volumes available for academic researchers from aids the secondary porosity by dissolution and creation of de Petroleum Nacional Agency (ANP) at the LISG- it” UNESPetro-UNESP. The database is formed by 2D and 3D seismic data in a total area of 850 Km², in 8 bits, and At the case of erosive processes, it may be originated by well data information of 20 wells. environment changes as marine regressions or by gravitational mechanism as submarine flux of rock. This The basement geometry was defined based on the effects change the topography’s geometry, but it can be gravimetric map of the CPRM. Based on the geographical reproduced in paleo-environment maps. position of the trend Linguado-Trilha and Pampo, a qualitative analysis about the presence of basement highs Among other factors, it is widely known that the tectonic and its relationship with the existence of carbonatic processes are the main factor that deforms stratigraphic reservoirs: Aptian and Albian, were done; this analysis is layers in sedimentary basins as Campos, Santos and justified because, it is possible that the evolution of any Espirito Santo; this condition justified the cinematic carbonate shoal is conditioned by the presence of analysis of its paleo-environment evolution. These basins basement paleo-highs. initially were deformed by the rift phase and after an intense halokinetic deformation was register, dated by With the aim of verify the regional distribution of the main Vincentelli & Barbosa (2008) from Upper Albian (about carbonate reservoirs: Albian (Calcarenites- Quissamã 100 My) to the Miocene (35 My). The mentioned authors Fm.) and Aptian (“Coquines” – Lagoa Feia Fm, regional also say that the halokinetic deformation was not continue geological sections were elaborated and its geographic along the geological time, but it defined geometries in the position was defined based on the gravimetric map of the basin that created accommodation spaces that allowed three study basins. These geological sections allowed the the turbiditic bodies (main recognized reservoir at the basement paleo-highs visualization, geological feature basins) sedimentation. that may condition the “Coquina” reservoir distribution. By

Fifteenth International Congress of the Brazilian Geophysical Society VINCENTELLI, M.G; CONTRERAS, S.; HABERMANN,L. 3 the use of back-stripping technique it is expected to on seismic interpretation. It is important to mention that reproduce the environment conditions that define the for Aptian age the main carbonate reservoirs for these “Coquina” as reservoir (when de permo-porous system is basins were recognized until now. interconnected), or when the “Coquina” is found as a rework rock without reservoir conditions. The Albian regional map indicates that the carbonate banks are absent at the distal portion of the basins, At the seismic interpretation, six stratigraphic level were mainly at the deep and ultra-deep water regions, mainly mapped: Lagoa Feia Fm. top, salt top, Albian top, Upper dislocated by the salt domes that configure two bands: top (Maastrichtian), Oligocene-Miocene (blue one at the proximal region that covers the Central High at mark) and Sea Bottom. After, the seismic sections were Santos Basin – position that is different at Campos and time to depth converted using interval velocities and the Espirito Santo were the salt domes are localized – and geological section was retrodeformed with the aim of another distal, located at the deep water in a band from verify if the currently basement structural highs were the Santos to Campos Basin, with total absence of Albian same in the Aptian age. Evidence of marine level because two factors: an hiatus of the sequence or transgressions at the identified paleo-lakes and available movement of the carbonate blocks caused by halokinetics spaces for sedimentation was also considered. at these two basins. Contour structural maps at the region of Badejo High, Results indicates: the structural traps are associated with the carbonate´s bank evolution for the Albian (Macaé Group – The figure 3 shows a geophysical section through the Figure 4) and for Lagoa Feia Gr (Aptian – figure 5). The onshore and offshore regions of Espirito Santo Basin. main azimuth of the carbonate banks is N15W and This section shows the Proterozoic domain at the N35wm and the system faults shows the main azimuth outcropping area, with a detachment fault of the NE-SW related to the rift phase. compressive phase associated with this geological age. The mentioned geological feature is limited by the boarder fault that separates the onshore to the offshore tectonics domains. The continuity of the Miocene reflector is observed at both domains and the deformation of the basement at the phase rift is clear at the interpreted horst structures. Nevertheless, the thickness of the rift sequence appear to be not too thick to development coquine reservoir facies at the Aptian of Espirito Santo Basin, in another words this place does not represent the same geological characteristics of the trend Linguado- Badejo-Pampo.

Figure 4.- Albian (Macaé Group) Contour structural map at the region of Badejo High. (hot colors at the map represents structural highs)

Figure 3. Seismic line showing a main basement horst identified at Espirito Santo Basin. Figure 3-B. Geophysical- Geological profile A (onshore) - A´(offshore), that shows the basement high at Espirito Santo basin equivalent to Badejo High, and the configuration of the basement deformation.

At the regional interpretation involving the three basins it was verified: a.- the presence of a proximal high confirmed at the gravimetric map; b.- The rift structures deforming stratigraphic levels older than Aptian; c.- the ends of the Aptian age is represented by a transition phase identified at the literature as “sag”(Winter , 2007). Figure 5.- Aptian (Lagoa Feia Group) Contour structural map at the region of Badejo High. (hot colors at the map The South of the study area (Santos Basin) shows a represents structural highs) Proximal and Central basement to Aptian highs identified

Fifteenth International Congress of the Brazilian Geophysical Society REGIONAL PALEO-ENVIRONMENTS AT APTIAN COQUINE RESERVOIRS ______4

The structural pattern observed at the top of Cabiúnas the higher position of a previous paleo-basement high, Formation (Figure 6) indicates a general dip EWE with a geological condition favorable to the main reservoir fault system with NE-SW direction. These features are evolution, but its oil volume is less than the Pre-salt related to the Gondwana Supercontinent fragmentation reservoirs because its structural dimension. initialized at Upper . An secondary faults system, with azimuth WNW-ESE, is also observed and represents As defined by Vincentelli et al. (2016), the Alegre fault at transfer zones generated for the extensional process own its offshore position, shows a sinistral movement for the of the continent´s separation. rift section at Campos Basin Campos (North) and shows neotectonic reactivation. This fault separates two oil provinces (the trend Linguado-Badejo-Pampo from Parque das Baleias region).

Figure 6: Contour Structural map of Cabiunas Formation at the region of Badejo High. When evaluated the tectonic-structural context at the rift Figure 7. Map of Bouguer Anomaly from CPRM (Meisling, phase of Santos, Campos and Espirito Santo basins – 2001), Campos and Santos Basins. With structural highs using geophysical data, potential maps methods defined by Rangel & Martins (1998) and system faults (gravimetric map – Bouguer Anomalies) and seismic data, defined by Vincentelli et al. (2016). integrated with ANP data and “informal” communication The map shows the Santos Basin at the South and Campos like conferences and non-technical journals, among basin at the North. The highlighted squares areas show the others, about oil fields and potential reservoirs Aptian main identified carbonate reservoirs at Aptian ages: Blue levels; It is possible to define mainly three production dark –Jubarte oil field (at North region) and Búzios oil field; hydrocarbon systems with its area indicated at the blue light –Libra field; green – Lula/Sapinhoá. The main anomalies represents: Moho closed to the coast (MU); squares of the figure 7: footwall blocks while Ocean Opening (FS). The main transfer faults (TZ). a.- Reservoirs in limestone – “Coquines” with good permeability and oil production initialized: Another structural limit of petroleum provinces is defined by Marlin fault as characterized by Vincentelli et a.1.- Black square: area of the trend Linguado- al. (2016), this structural feature represents the structural Badejo- Pampo. limit between the Badejo High and the Corvina- Parati Low as defined by Rangel and Martins (1998). At a.2.- Blue dark squares: upper square, area of the Southeast of Marlim fault turbidites reservoirs are the Jubarte –Espirito Santo Basin - oil field; lower square, dominant play. Buzios – Santos Basin). Conclusions b.- Reservoirs in limestone “Coquines” without initialized oil production – blue light square: Libra oil field. The seismic data interpretation and regional maps show the same structural patterns; with the main faults normal c.- Carbonates type limestone: stromatolites and showing an azimuth of NE-SW, and transfer fault zones laminated microbialites – green square: area of oriented NW-SE. At the Southwest portion of the study Lula and Sapinhoá fields. area an important dome feature was characterized at Quissama Formation level (Albian) and it corresponds to Until now two of these production poles are reference in Pampo Dome. A similar structure but in less scale was Brazil: the traditional one is related to Badejo High identified at the South of Bonito oil field, associated with (Rangel & Martins, 1998, Figure 7), where the main normal synthetic and antithetic faults that condition the oil reservoir shows high porosity and permeability mainly at production at this field. It was also possible the Pampo oil field, with oil production until today, localized at identification of fault system that affected the Aptian level

Fifteenth International Congress of the Brazilian Geophysical Society VINCENTELLI, M.G; CONTRERAS, S.; HABERMANN,L. 5 and the Post-Salt section exemplified at the fault that separates the fields Bicudo – Pampo and Badejo – Trilha; it was interpretded that this fault system were determinant for the oil migration at the basin from the Jiquia to the Aptian-Coquines and upper reservoirs. The regional seismic interpretation verified: a.- the presence of a proximal high confirmed at the gravimetric map; b.- The rift structures deforming stratigraphic levels older than Aptian; c.- the ends of the Aptian age is represented by a transition phase identified at the literature as “sag”. When evaluated the tectonic-structural context at the rift phase using geophysical data gravimetric map (Bouguer Anomalies) and seismic data, it is possible to define mainly three production hydrocarbon systems: a.- Reservoirs in limestone – “Coquines” with good permeability and oil production initialized; b.- Reservoirs in limestone “Coquines” without initialized oil production; and, c.-Carbonates type limestone: stromatolites and laminated microbialites. Finally, the identification of a fault system that affected the Aptian level and the Post-Salt section were determinant for the oil migration at the basin, from the Jiquia Formation to the Aptian-Coquines and upper reservoirs.

Acknowledgments This research was development at UNESPetro, Center of Geosciences Applied to Petroleum, UNESP, IGCE, Rio Claro – SP – Brazil.

References

CASTRO, J. C. Evolução dos conhecimentos sobre as coquinas-reservatório da Formação Lagoa Feia no Trend Badejo-Linguado-Pampo, Bacia de Campos. Revista Geociências, Rio Claro, v. 25, p. 175-186, 2006.

RANGEL, H.D. & MARTINS, C.C. Principais compartimentos exploratórios, Bacia de Campos. In: (ed.) Searching for Oil and Gas in the Land of Giants. Rio de Janeiro. Schlumberger p.32-40. 1998.

Vincentelli C, M. G.; NEVES, M. ; MORALES, N. Controle Estrutural do Neógeno e Quaternario nas Bacias de Campos e Do Espírito Santo. Geociências. Vol. 35, #1, 2016.

Winter W.R., Jahnert R.J., França A.B. 2007. Bacia de Campos. Boletim de Geociências da , 15:511- 529.

Fifteenth International Congress of the Brazilian Geophysical Society